Practice question · Multiple choice
A shift register moves every bit one place per clock and is used for serial-to-parallel conversion. What problem is it solving?
Hints
- Ask what a 32-bit parallel connection costs in pins and traces compared with a serial one.
- The data arrives one bit at a time. What has to happen before the word is usable?
Show the answer
B. Trading time for wires, one bit per clock accumulated into a word
Why
Pins and board traces are expensive, so serial links send bits over time and the shift register reassembles them into a word, time traded for wires. It is why USB, SATA and PCIe are serial despite sounding slower, and why every one of them has a shift register at each end.
Practise Flip-Flops and Registers
The app has 7 more questions on this lesson, and keeps your place in the course. Computer Science I is free to start.